Natural Selection Observed

This has been started because some creationists do not accept Natural Selection. It is not an attempt at equivocation. I will not use this to springboard an argument into macro-evolution.

This shows Darwinism in action at the micro-evolutionary scale to such a degree that no-one could really deny it I think.

This all happens within the 'Fish' Kind.

This example is taken from Ã¢â‚¬Å“The Greatest Show on Earth by Richard Dawkins.

First, an anecdote from the book:

My colleague Dr John Endler, recently moved from North America to the University of Exeter, told me the following marvellous - well, also depressing - story. He was travelling on a domestic flight in the United States, and the passenger in the next seat made conversation by asking him what he did. Endler replied that he was a professor of biology, doing research on wild guppy populations in Trinidad. The man became increasingly interested in the research and asked many questions. Intrigued by the elegance of the theory that seemed to underlie the experiments, he asked Endler what that theory was, and who originated it. Only then did Dr Endler drop what he correctly guessed would be his bombshell: 'It's called Darwin's theory of evolution by natural selection!' The man's whole demeanour instantly changed. His face went red; abruptly, he turned away, refused to speak further and terminated what had hitherto been an amiable conversation. More than amiable, indeed: Dr Endler writes to me that the man had 'asked some excellent questions before this, indicating that he was enthusiastically and intellectually following the argument. This is really tragic.'

What did Endler do? He took some wild guppies Poecilia reticulata which in the wild have Ã¢â‚¬Ëœstriking variationÃ¢â‚¬â„¢ in loal populations. Some were almost as bright as the aquarium versions, and he thought that they must have been s*xually selected for. This is the important point, he tested this hypothesis! He didnÃ¢â‚¬â„¢t just assume it.

Others were more plain and matched the rocky bed of the tributaries that they lived in, and he thoiught they were camoflagued to hide from predators, but again, he wanted to test this hypothesis.

He took some of these guppies back to the lab and put them in tanks with various bottoms, such as sand and gravel and different levels of predation from fish such as pike cichlid, Crenicichla alta, which is its natural predator.

He also had some put in with the Killifish ( Rivulus hartii) which is a weak predator, and with different layers on the bottom.

In another set of tanks were guppies with no predation, but the same layers along the bottom.

He saw the species change in 6 months (in spot number, size and the colour depending on whether the selection was the Cichlid, the Killifish or the female), and he then took some of these back and put them into a tributary with only killifish and checked on them two years later and they were already more brightly coloured.

This is only a quick summary of the detail. I couldnÃ¢â‚¬â„¢t do it justice, but nine years later, another researcher found the descendants of EndlerÃ¢â‚¬â„¢s introduced guppies and they were as brightly coloured as ever.

1) I have assumed that all the information was present in the fish to start with. Not empirical in the slightest, but an a priori assumption from my point of view.

2) I do not completely rule out God changing the colours of the fish, but find that does not fit in well with what I know of scripture. My reading of scripture is that God is immanent in creation, not guiding it (a subtle but important difference). The word for create used in Genesis 1 and 2 (I can't remember what the Hebrew is) is different to the word translated as create later in the Bible, showing that God was after that point upholding the creation rather than [sorry had to google it - my Hebrew isn't what it once was] 'bara' on an ongoing basis.

3) The main reason is a census of the tanks recorded the amount of predation, which confirmed the cichllid as the best predator, and the only form of selection that could have made the ones with little or no predation would have been S@xual selection.

1. survival: a natural process resulting in the evolution of organisms best adapted to the environment

2. A process in nature in which organisms possessing certain genotypic characteristics that make them better adjusted to an environment tend to survive, reproduce, increase in number or frequency, and therefore, are able to transmit and perpetuate their essential genotypic qualities to succeeding generations.

See definitions, especially the bolded.

Yet this is not what you have provided.

You have provided an apparent experiment committed by a man in his lab. This is not a natural process or nature, this is man making his own experiment...

Can you provide an example of observed natural selection in nature, and not a test laboratory?

Imitating a river environment in a lab is as near as make no odds to being in a river. The devil is in the detail. If they did it in little aquariums, I would agree with you. If they tried to copy the wild habitat then you are wrong.

Guess which of these they used:

1) Simple fish tank2) Try and recreate the natural environment.

You are splitting hairs, and trying to find any way that will mean you don't have to accept the consequences of this experiment.

plus they did the same experiment in the wild!

Read what I write and don't take my word for it. Look up the original research because the details will be in there.

It seems you are trying everything in your ability to refuse to accept this because your philosophy does not allow it. This is nothing about the evidence and all about you not wanting to accept even micro-evolution.

Did you say on another thread that evolution isn't science "since it's not "observable. testable or measurable"

If you want to prove 'natural selection' (nature selecting) you would need observable evidence from nature.

Speciation has been observed within our lifetime. If you are going to argue that such steps cannot accumulate into macroevolution I would be interested to hear why. I have provided links in the past but the only answer is "fish only ever births fish" thus ignoring the incremental change in the (diverging) population.

Let's try to find then some common ground on this. We know the definition of ''natural selection'', to re-paste:

''survival: a natural process resulting in the evolution of organisms best adapted to the environment''

Note the 'natural process' in the definition. The idea of natural selection is based on nature (random or undirected, but still nature).

That is your definition, and NOT the one we both agreed on in the "Hi" thread about Darwinism:

1. More children are born than can survive into adulthood.2. Not all children are the same, ie there is variation in the offspring.2. The ones that survive are generally the ones most fitted to their environment.3. These survivors will have children more likely to survive.

This is the definition of Natural Selection as taken from On the Origin of Species and which yoiu agreed was accurate.

It provides a mechanism for the change here.

For this to be observed where would you simply need to be?

In the natural environment.

You can't 'replicate' nature in a test laboratory or an environment made by man because that would not not-natural and artificial.

If you want to prove 'natural selection' (nature selecting) you would need observable evidence from nature

READ MY POST! They also did the same experiment in the wild and up to nine years later. This destroys your argument that it hasn't been done in the wild.

But even if they did it in the lab, it still counts because they are testing only whether the pike cichlids, killifish and S@xual selection can affect a population without human intervention (after putting them in the tanks). The experiment was carried out brilliantly (read the book I mention at the start or look at their original research) to show the actual details of how they set out the experiment.

It is very revealing, but I do not have the time to write any more than the quick summary that I provided in the OP. It would be unfair to attack their methodology and say that the lab setting wasn't done to a realistic enough standard based on my summary.

If during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organisation, and I think this cannot be disputed; if there be, owing to the high geometrical powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each being's own welfare, in the same way as so many variations have occurred useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterised. This principle of preservation, I have called, for the sake of brevity, Natural Selection

I will ask again whether you read what I post?

In Darwin's words, that you said you agreed with, I'm guessing that you didn't read it properly.

You so far still have not provided any natural observational evidence for it.

They shiowed the same effect shown in the lab actually in a tributary near where they originally got the guppys from, and nine years later some other people went and confirmed the results.

Umm isn't there that one with the black and grey moths and how the grey ones could hide on the bark easier, and the black ones could hide easier after coal was used in the industrial revolution, (which made the trees sooty)...

This fits nicely in the creation model; micro-evolution >=< adaptation.

I'm sorry PhilC, this topic doesn't offer anything new

I have to agree. Darwin gave us natural selection--no doubt. But his finches' beaks revert back according to environment.

The unknown part of his theory was pangenesis, which long story short was Lamarkian. A belief that acquired traits were passed on. Little wonder this caught fire in higher thinking, that is until they rediscovered Mendel's (a creationist) work, and rejected LaMarkian evolution.

But at any rate they had had thirty years to root the love affair with evolution in higher education.

Now we have people like PhilC trying to convince us that adaptation justifies an inference of macro evolution.

Umm isn't there that one with the black and grey moths and how the grey ones could hide on the bark easier, and the black ones could hide easier after coal was used in the industrial revolution, (which made the trees sooty)...

However, yes the moths have changed colour... They are still moths

Not only that, but light colored moths are found in higher frequency than dark colored moths in polluted areas and vica versa.